Wireless communications devices such as cellular devices are become prevalent in security systems for reporting the status of the systems to a remote device. The integrity of a system is dependent on a 100% availability of a communication path between the wireless communications device and the remote device. With a single communications path wireless system, 100% availability cannot be guaranteed, due to noise within the communication path or other attenuation electromagnetic characteristics of the surrounding environment. Therefore, a redundant communications path is needed. In fact, in UL listed communications systems for reporting fire alarms, two separate communications paths are required. Each of the communications paths must be periodically tested. A test call is placed periodically (e.g. once daily) to ensure that the two connections are operating properly in the event that a real fire had to be reported.
Wireless devices, such as a cellular device provides a unique problem, as the device typically is only capable of communicating over one communications path. Specifically, a cellular telephone is programmed to communicate through only one cell base station and not to communicate through two separate cell base stations.
U.S. Pat. No. 7,177,639, issued to Winick et al., on Feb. 13, 2007, assigned to Honeywell International, Inc., describes a dual site supervision for a control channel cellular radio for a fire alarm reporting system that uses logic that causes the normal control channel cellular transceiver to operate in a nonstandard manner and to use a different and second cellular base station that the unit would normally not select operating pursuant to a standard cell phone software module.
However, there is still a need to have a wireless device adapted for communication with two independent and distinct networks or carriers that ensures that a communications path to a remote site is always available.